public class t1<T> {
    private T num;

    public T getNum() {
        return num;
    }

    public void setNum(T num) {
        this.num = num;
    }


    private static <T> T test(Object s, Integer a, Class<T> bb, Class aa) {
        System.out.println((T) s);
        return (T) s;
    }

    public static void main(String[] args) {
        test("aa", 2, Integer.class, String.class);
        Object o=new String("aa");
        System.out.println(o.getClass());
    }
}
